Table 3.

Summary of rodent studies exploring the link between the HPA axis and depression-like behavior. In general, manipulations that increase HPA axis tone promote depressive behaviors, whereas manipulations that limit HPA axis tone reduce or prevent them. FST = forced swim test; SPT = sucrose preference test; CRH = corticotropin releasing hormone; GC = glucocorticoid.

HPA manipulation	Test	Behavioral Outcome	References
Increased CRH or GC signaling (Receptor agonist, transgenic mice)	FST SPT	↑ immobility ↓ sucrose intake	(137, 168, 381) (181)
Chronic stress-induced increases in CRH and GC signaling (Homotypic or heterotypic stress paradigms)	FST SPT	↑ immobility ↓ sucrose intake	(1, 197, 271, 351, 352, 409, 534) (197, 215, 347, 409, 534, 585, 586)
Reduced CRH or GC signaling during/after chronic stress (Receptor antagonists, adrenalectomy)	FST SPT	↓ immobility ↑ sucrose intake	(511, 567, 600) (181, 599)